Absorbing body and absorbent article

Abstract

In an absorbent containing a highly absorbent polymer, improved fit during wear is achieved while maintaining thinness. An absorbent has mutually orthogonal length, width, and thickness directions, and comprises a substrate sheet and a highly absorbent polymer laminated thereon. The absorbent has a high unit area weight region where the unit area weight of the highly absorbent polymer is higher than its surroundings. This high unit area weight region is arranged such that points representing the maximum thickness in the thickness direction are intermittently positioned in the length and width directions, the maximum thickness being 3 mm or less, and the spacing between adjacent points representing the maximum thickness is 5 times or less than the maximum thickness.

Description

Technical Field

[0001] This invention relates to absorbents and absorbent articles. Background Technology

[0002] Conventional absorbent articles, such as disposable diapers, have existed with absorbent bodies that possess liquid absorbency. Among such absorbent bodies, SAP sheets containing a highly absorbent polymer (so-called SAP) and not containing fibrous materials such as pulp are known. Such SAP sheets are easier to reduce in thickness compared to absorbent bodies containing fibrous materials, and are therefore suitable for forming thin absorbent bodies. For example, Patent Document 1 discloses an absorbent body in which a highly absorbent polymer is disposed in a sheet material.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2023-122342 Summary of the Invention

[0006] The problem the invention aims to solve

[0007] In the SAP sheet (absorbent) described in Patent Document 1, a large number of SAP particles are stacked on a material sheet (substrate sheet) in a uniform thickness. However, there are concerns about such SAP sheets, for example, when they are sandwiched between the wearer's legs (i.e., the groin area) during wear, they are difficult to conform to the contours of the wearer's body, resulting in poor fit.

[0008] The present invention was made in view of the aforementioned problems, and its object is to improve the fit when worn while maintaining the thinness of the absorbent (SAP sheet) having a highly absorbent polymer.

[0009] Solution for solving the problem

[0010] The main invention for achieving the above objective is an absorbent having mutually orthogonal length, width, and thickness directions, and having a substrate sheet and a highly absorbent polymer laminated on the substrate sheet. The absorbent is characterized by having a high unit area weight region where the weight per unit area of ​​the highly absorbent polymer is higher than the surrounding area. This high unit area weight region is arranged such that points becoming the maximum thickness in the thickness direction are intermittently positioned in the length and width directions, the maximum thickness being less than 3 mm, and the interval between adjacent points becoming the maximum thickness is less than 5 times the maximum thickness.

[0011] Other features of the invention will become clear from the description in this specification and the accompanying drawings.

[0012] The effects of the invention

[0013] According to the present invention, in an absorbent having a highly absorbent polymer, it is possible to improve the fit when worn while maintaining thinness. Attached Figure Description

[0014] Figure 1 This is a rough 3D diagram of Diaper 1.

[0015] Figure 2 This is a top view of the diaper 1 in its unfolded and elongated state, observed from the skin side.

[0016] Figure 3 yes Figure 2 A schematic cross-sectional view at the center line CL.

[0017] Figure 4 of Figure 4 A is a cross-sectional schematic diagram of absorber 20. Figure 4 of Figure 4 B is a cross-sectional schematic diagram of absorber 20A showing details of SAP layer 27.

[0018] Figure 5 This is a top view of absorber 20A.

[0019] Figure 6 of Figure 6 A is a cross-sectional schematic diagram showing the case where 14 layers of highly absorbent polymer are stacked on a substrate sheet. Figure 6 of Figure 6 B is a top view showing the recessed area 214F on one side of the substrate sheet 14.

[0020] Figure 7 of Figure 7 A is a cross-sectional schematic diagram showing the state of absorber 20A before it absorbs moisture. Figure 7 of Figure 7 B is a cross-sectional schematic diagram showing the state of absorber 20A after absorbing water.

[0021] Figure 8 This is a top view schematic diagram of the absorber 20B of the modified example.

[0022] Figure 9 This is a schematic diagram showing the outline of the absorber manufacturing apparatus 50.

[0023] Figure 10 This is a diagram illustrating the suction opening 11su of the suction section 11P.

[0024] Figure 11 of Figure 11 A is a partial cross-sectional view of the conveyor belt 11 cm. Figure 11 of Figure 11B is a top view of a portion of the conveyor belt 11 cm.

[0025] Figure 12 This is a top view schematic diagram showing another example of the suction opening su of the suction section 11P.

[0026] Figure 13 This diagram illustrates the supply of SAP particles and the discharge of adhesive in the absorbent manufacturing apparatus 50.

[0027] Figure 14 This is a diagram illustrating the suction opening 11su in the absorber manufacturing apparatus 50A of the first modified example.

[0028] Figure 15 This is a schematic diagram showing the outline of the absorber manufacturing apparatus 60.

[0029] Figure 16 This is a diagram illustrating the plate portion 11pt of the conveyor section 11y.

[0030] Figure 17 This is a top view schematic diagram showing another example of a 11pt plate.

[0031] Figure 18 This diagram illustrates the supply of SAP particles and the discharge of adhesive in the absorbent manufacturing apparatus 60.

[0032] Figure 19 This is a perspective view of the absorber manufacturing apparatus 60A of the second modification.

[0033] Figure 20 This is a top view schematic diagram showing another example of a substrate 118 with a plate portion of 11pt.

[0034] Figure 21 This is a perspective view of the absorber manufacturing apparatus 60B of the third modification. Detailed Implementation

[0035] Based on the description in this specification and the accompanying drawings, at least the following matters become clear.

[0036] (Method 1)

[0037] An absorber having mutually orthogonal length, width, and thickness directions, and having a substrate sheet and a highly absorbent polymer laminated on the substrate sheet, characterized in that the absorber has a high unit area weight region where the weight per unit area of ​​the highly absorbent polymer is higher than that of the surrounding area, the high unit area weight region being arranged such that points becoming the maximum thickness in the thickness direction are intermittently located in the length and width directions, the maximum thickness being less than 3 mm, and the spacing between adjacent points becoming the maximum thickness being less than 5 times the maximum thickness.

[0038] According to Method 1, high weight-per-unit-area areas are configured by intermittently positioning points that represent the maximum thickness in the thickness direction along the length and width directions, and low weight-per-unit-area areas are formed around each high weight-per-unit-area area area. For the absorbent, the low weight-per-unit-area areas serve as bending points, facilitating easy deformation along the contours of the wearer's body and improving fit. Furthermore, the maximum thickness of the absorbent is less than 3 mm, and the spacing between adjacent points representing the maximum thickness is less than 5 times the maximum thickness. This allows for the configuration of a large number of high weight-per-unit-area areas and a large number of low weight-per-unit-area areas while maintaining the thinness of the absorbent. Therefore, according to Method 1, in an absorbent with a highly absorbent polymer, it is possible to improve fit while maintaining thinness.

[0039] (Method 2)

[0040] An absorber, as described in Method 1, is characterized in that the maximum thickness is within 2 mm, and the interval between adjacent points that constitute the maximum thickness is less than 4 times the maximum thickness.

[0041] According to method 2, in an absorbent with a highly absorbent polymer, the fit during wear can be further improved while maintaining thinness.

[0042] (Method 3)

[0043] An absorber, which is the absorber described in Method 1 or Method 2, is characterized in that the high weight-per-unit area region does not contain fibrous materials other than the highly absorbent polymer.

[0044] According to method 3, it is possible to form a thinner absorber compared to an absorber containing fibrous material.

[0045] (Method 4)

[0046] An absorber, which is the absorber described in any of the methods 1 to 3, is characterized in that, when viewed from above, the diameter of the circumscribed circle that is circumscribed to each of the plurality of high unit area weight regions is 2 mm or more and 4 mm or less.

[0047] According to method 4, by reducing the size of each of the multiple high weight-per-unit area regions when viewed from above, a large number of high weight-per-unit area regions and a large number of low weight-per-unit area regions can be arranged on the substrate sheet, and the absorber can easily deform along the contours of the wearer's body, thereby improving fit.

[0048] (Method 5)

[0049] An absorber, which is the absorber described in any of embodiments 1 to 4, is characterized in that the absorber has: a low unit area weight stacked region in which the highly absorbent polymer is stacked between adjacent points that constitute the maximum thickness; and a non-stacked region in which the highly absorbent polymer is not present between other adjacent points that constitute the maximum thickness.

[0050] According to method 5, the low weight-per-unit area region, which serves as the starting point for bending, has a low weight-per-unit area layered region capable of absorbing and retaining excrement, and a non-layered region that is easier to bend due to the absence of highly absorbent polymers. Therefore, even in the low weight-per-unit area region, it is possible to balance ease of deformation along the contours of the wearer's body with the ability to absorb and retain excrement.

[0051] (Method 6)

[0052] An absorber, as described in embodiment 5, is characterized in that the low unit area weight stacked regions are discontinuously arranged in the length direction and the width direction, and the non-stacked regions are discontinuously arranged in the length direction and the width direction.

[0053] According to method 6, by sparsely arranging the low unit area weight stacked and non-stacked areas on a plane, it is possible to have expandable deformability along the contours of the wearer's body and absorbent retention of excrement on the plane.

[0054] (Method 7)

[0055] An absorber, as described in Method 6, is characterized in that, when viewed from above, the largest diameter of the inscribed circles that are internally tangent to the plurality of said non-overlapping regions is less than or equal to the maximum thickness.

[0056] According to method 7, by reducing the size of the non-laminated regions where there is no highly absorbent polymer when viewed from above, leakage of the excrement through the non-laminated regions can be suppressed.

[0057] (Method 8)

[0058] An absorber, as described in embodiment 6 or 7, is characterized in that the number of the low unit area weight stacked regions differs in each region trisected along the length direction, or the number of the non-stacked regions differs in each region trisected along the length direction.

[0059] According to method 8, by irregularly arranging the low unit area weight layered and non-layered areas on a plane, the absorbent body can easily deform along the contours of the wearer's body, thereby improving fit.

[0060] (Method 9)

[0061] An absorber, which is the absorber described in any of embodiments 6 to 8, is characterized in that, among the points that become the maximum thickness, the number of points located adjacent to the non-stacked region on one or the other side of the width direction is greater than the number of points located adjacent to the non-stacked region on one or the other side of the length direction.

[0062] According to method 9, it is possible to suppress the situation where the absorbent loses its flexibility in the width direction when it is in a swollen state.

[0063] (Method 10)

[0064] An absorbent, as described in any of embodiments 1 to 9, is characterized in that it has an additional sheet positioned such that the highly absorbent polymer is sandwiched between the absorbent and the substrate sheet, the absorbent having: a bonding region in which the substrate sheet and the additional sheet are bonded together at adjacent points that constitute the maximum thickness; and a non-bonding region in which the substrate sheet and the additional sheet are not bonded together at other adjacent points that constitute the maximum thickness.

[0065] According to method 10, by having a bonding area that serves as the starting point of bending and a non-bonding area where a highly absorbent polymer can be disposed between the substrate sheet and another sheet, it is possible to balance the ease of deformation along the contours of the wearer's body with the absorption and retention of excrement.

[0066] (Method 11)

[0067] An absorber, which is the absorber described in any of the embodiments 1 to 10, is characterized in that the difference between the highest point and the lowest point in the thickness direction on one side of the substrate sheet is different from the difference on the other side of the substrate sheet.

[0068] According to method 11, an absorber with properties corresponding to the purpose can be formed.

[0069] (Method 12)

[0070] An absorber, as described in embodiment 11, is characterized in that, on one side of the substrate sheet, there are non-stacked regions between adjacent points that constitute the maximum thickness, where the highly absorbent polymer is absent, and when viewed from above, the largest diameter of the inscribed circles that are inscribed within the plurality of said non-stacked regions is less than or equal to the difference on the one side.

[0071] According to method 12, by reducing the size of the non-laminated regions where there is no highly absorbent polymer when viewed from above, leakage of the excrement through the non-laminated regions can be suppressed.

[0072] (Method 13)

[0073] An absorber, which is the absorber described in embodiment 11 or 12, is characterized in that, on one side of the substrate sheet, the weight of the highly absorbent polymer laminated below the highest point is more than 50% of the weight of the highly absorbent polymer laminated on the entire substrate sheet.

[0074] According to method 13, by laminating a desired weight of highly absorbent polymer onto the recessed area of ​​the substrate sheet, a high weight-per-unit-area region can be formed at the appropriate location.

[0075] (Method 14)

[0076] An absorber, which is the absorber described in any of embodiments 11 to 13, is characterized in that, when a region located below the midpoint between the highest point and the lowest point is designated as a recessed region, when viewed from above, the total length of the plurality of recessed regions along an imaginary line passing through the center of the plurality of recessed regions in the length direction is more than 50% of the overall length of the substrate sheet.

[0077] According to method 14, by laminating a highly absorbent polymer onto a desired area of ​​a substrate sheet, it is possible to form high weight-per-unit area areas and low weight-per-unit area areas at appropriate locations.

[0078] (Method 15)

[0079] An absorber, which is the absorber described in any of embodiments 11 to 14, is characterized in that, when a region located below the midpoint between the highest point and the lowest point is designated as a recessed region, when viewed from above, the total length of the plurality of recessed regions is at least 50% of the overall length of the substrate sheet on an imaginary line passing through the center of the plurality of recessed regions along the width direction.

[0080] According to method 15, by laminating a highly absorbent polymer onto a desired area of ​​a substrate sheet, it is possible to form high weight-per-unit area areas and low weight-per-unit area areas at appropriate locations.

[0081] (Method 16)

[0082] An absorber, which is the absorber described in any of embodiments 1 to 15, is characterized in that the absorber has a channel region in which the weight per unit area of ​​the highly absorbent polymer is lower than that of the region with a high weight per unit area, the channel region extending along the length direction, and in the width direction, the width of the channel region being greater than the interval between adjacent points that constitute the maximum thickness.

[0083] According to method 16, the groove area becomes the starting point of bending, and it is easy to deform along the width direction at the crotch of the wearer, which enhances the storage capacity at the crotch and further improves the fit.

[0084] (Method 17)

[0085] An absorber, as described in embodiment 16, is characterized in that the channel region is provided with a plurality of channels in the width direction.

[0086] According to method 17, the storage capacity of the crotch area is further enhanced, and the fit is further improved.

[0087] (Method 18)

[0088] An absorbent, which is the absorbent described in any of embodiments 1 to 17, is characterized in that the absorbent has an additional sheet positioned such that the highly absorbent polymer is sandwiched between the absorbent and the substrate sheet, wherein the additional sheet and the substrate sheet are joined together in the thickness direction at a location further outward than the region where the highly absorbent polymer is disposed.

[0089] According to method 18, it is possible to suppress openings between the substrate sheet and other sheets.

[0090] (Method 19)

[0091] An absorbent, which is the absorbent described in any of the embodiments 1 to 18, is characterized in that an adhesive is provided between the substrate sheet and the highly absorbent polymer in the thickness direction.

[0092] According to method 19, the highly absorbent polymer can be reliably fixed relative to the substrate sheet.

[0093] (Method 20)

[0094] An absorbent, which is the absorbent described in any of the embodiments 1 to 19, is characterized in that, in the thickness direction, it has a fibrous material comprising pulp at a position adjacent to the highly absorbent polymer.

[0095] According to method 20, it can quickly and temporarily absorb the excrement and suppress the overflow and leakage of the excrement during excretion.

[0096] (Method 21)

[0097] An absorbent, which is the absorbent described in any of the embodiments 1 to 20, is characterized in that an adhesive is provided between the fibrous material and the highly absorbent polymer in the thickness direction.

[0098] According to method 21, fibrous materials can be fixed.

[0099] (Method 22)

[0100] An absorbent article having mutually orthogonal length, width, and thickness directions in its unfolded state, and having an absorbent body comprising an absorbent core, a substrate sheet, and a highly absorbent polymer laminated on the substrate sheet, characterized in that the absorbent body has a high unit area weight region where the unit area weight of the highly absorbent polymer is higher than the surrounding area, the high unit area weight region being arranged such that points becoming the maximum thickness in the thickness direction are intermittently positioned in the length and width directions, the maximum thickness being within 3 mm, and the interval between adjacent points becoming the maximum thickness being less than 5 times the maximum thickness.

[0101] According to method 22, it is possible to make an absorbent article having an absorbent body that can improve fit when worn while maintaining thinness.

[0102] ===Absorbent Items and Absorbent Bodies===

[0103] As an absorbent article of the present invention, a shorts-type disposable diaper 1 (hereinafter also referred to as "diaper 1") for infants and young children will be described as an example. However, the absorbent articles of the present invention also include strip-type disposable diapers, shorts-type sanitary napkins, absorbent pads, menstrual sanitary napkins, and other absorbent articles. In addition, the wearer of the absorbent article is not limited to infants and young children, but may also be an adult or an animal.

[0104] <<Structure of Absorbent Materials (Diaper 1)>>

[0105] Figure 1 This is a rough 3D diagram of Diaper 1. Figure 2 This is a top view of the diaper 1 in its unfolded and elongated state, observed from the skin side. Figure 3 yes Figure 2 A schematic cross-sectional view at the center line CL.

[0106] The "unfolded state" of diaper 1 refers to the state when the diaper is unfolded. Figure 1 The pair of side joints 2 located on both sides of the diaper 1 shown are separated and as follows: Figure 2The diaper 1 is opened and unfolded in a flat state as shown. The "stretched state" of the diaper 1 refers to the state in which the diaper 1 is stretched out without wrinkles. Specifically, it refers to the state in which the diaper 1 is stretched out to the point that the size of each component constituting the diaper 1 (such as the absorbent body 10, waist section 30, 40, etc., described later) is the same as or close to the size of the individual component.

[0107] like Figure 1 As shown, the diaper 1 has mutually orthogonal vertical, width, and front-back directions, and has a waist opening BH and a pair of leg openings LH. The upper side in the vertical direction corresponds to the waist opening BH side, and the lower side in the vertical direction corresponds to the crotch side. The front side in the front-back direction corresponds to the wearer's abdomen, and the back side in the front-back direction corresponds to the wearer's back. Figure 2 As shown, the width direction is along the direction of extension and retraction of the elastic members 33 and 43, such as the elastic bands provided on the front waist section 30 and the rear waist section 40. The vertical direction is along a direction orthogonal to the direction of extension and retraction.

[0108] Diaper 1 is a so-called three-piece shorts-type diaper consisting of a liquid-absorbing absorbent body 10 and a pair of waist sections 30 and 40. The waist section that covers the wearer's ventral side is referred to as the front waist section 30, and the waist section that covers the wearer's back side is referred to as the back waist section 40.

[0109] exist Figure 2 In the unfolded state shown, the diaper 1 has mutually orthogonal length, width, and thickness directions. The length direction is along the length of the absorbent body 10 and along the vertical direction of the shorts-type diaper 1. Figure 3 As shown, the thickness direction is the direction in which the materials constituting diaper 1 are stacked. The side in the thickness direction that comes into contact with the wearer's skin is designated as the skin side, and the opposite side is designated as the non-skin side.

[0110] In addition, Figure 2 In its unfolded state, with the front waist section 30 and the rear waist section 40 arranged parallel to each other at intervals along their length, an absorbent body 10 is positioned between them. Each end of the absorbent body 10 along its length is joined and fixed to the skin side of the closest waist sections 30 and 40, and its overall shape is approximately the letter H when viewed from above. Then, from this state, the absorbent body 10 is folded in half at its center line CL along its length. In this folded state, the opposing front waist sections 30 and rear waist sections 40 are joined and connected on their sides in the width direction, forming a pair of side joints 2. Furthermore, the side joints 2 are formed using known joining methods such as welding or bonding.

[0111] like Figure 3 As shown, the absorbent body 10 has an absorbent body 20 (details to follow), a liquid-permeable top sheet 12 disposed on the skin side of the absorbent body 20, and a back sheet 13 disposed on the non-skin side of the absorbent body 20. The back sheet 13 has a double-layer structure consisting of a liquid-impermeable sheet 13a and a hydrophobic outer sheet 13b disposed on the non-skin side of the liquid-impermeable sheet 13a. However, the absorbent body 10 may also have sheet components other than those described above. For example, a second sheet (not shown) may be provided in the thickness direction between the top sheet 12 and the absorbent body 20.

[0112] A pair of leak-proof wall portions 15 are provided on both sides of the absorbent body 10 in the width direction and along the length direction of the absorbent body 10. Figure 3 In the middle section, in the width direction, a portion of the outer sheet 13b extends outward from both ends of the absorbent body 20 and bends towards the skin at multiple locations, thereby forming a pair of leak-proof wall portions 15. An elastic member 16, such as an elastic band, is installed at the front end of the leak-proof wall portion 15, extending along the length direction of the absorbent body 10, and the leak-proof wall portion 15 is configured to stand upright towards the skin. Furthermore, elastic members 17, such as elastic bands, are installed on both sides of the absorbent body 10 in the width direction, extending along the length direction of the absorbent body 10.

[0113] like Figure 2 As shown, the front waist section 30 has skin-friendly side panels 31, non-skin-friendly side panels 32, and multiple elastic waistbands 33, while the rear waist section 40 has skin-friendly side panels 41, non-skin-friendly side panels 42, and multiple elastic waistbands 43. The multiple elastic waistbands 33 are arranged vertically between the skin-friendly side panels 31 and the non-skin-friendly side panels 32, and the multiple elastic waistbands 43 are arranged vertically between the skin-friendly side panels 41 and the non-skin-friendly side panels 42, and are installed in a state of elongation in the width direction. Through the elasticity of the elastic waistbands 33 and 43, the front waist section 30 and the rear waist section 40 fit snugly against the wearer's waist. Alternatively, the covers 34 and 44 may be configured to cover the upper end of the absorbent body 10 from the skin side. The covers 34 and 44 can be used to suppress openings in the absorbent body 10.

[0114] In addition, such as Figure 2As shown, the front waist section 30 and the rear waist section 40 have different planar shapes when unfolded and extended. The front waist section 30 has a length in the vertical direction approximately the same as the side joint 2, and is a rectangular shape that is longer in the width direction. The rear waist section 40 has a rectangular portion that overlaps with the front waist section 30, and a roughly trapezoidal portion 40E that extends downwards from the aforementioned portion. This extended portion 40E can cover the wearer's buttocks.

[0115] The above describes the basic structure of diaper 1, but the structure described above is an example and is not limited to this. For example, the front waist section 30 and the back waist section 40 may be formed by a single continuous member, or an external member may be provided in the crotch area to connect the front waist section 30 and the back waist section 40. Alternatively, the elastic members such as waist elastic members 33 and 43 may not be elastic bands, but sheet-like elastic members.

[0116] <<Structure of the Absorber>>

[0117] Next, based on Figure 4 A, Figure 4 B and Figure 5 Details of the absorbent element 20 in the above-mentioned absorbent article (diaper 1) will be explained.

[0118] Figure 4 A is a cross-sectional schematic diagram of absorber 20. Figure 4 B is a cross-sectional schematic diagram of absorber 20A showing details of SAP layer 27. Figure 5 This is a top view of absorber 20A.

[0119] like Figure 4 As shown in Figure A, the absorbent body 20 of the aforementioned absorbent article (diaper 1) has absorbent cores 21 to 23 between the skin-side core cover 24 and the non-skin-side core cover 25. The absorbent cores 21 to 23 are components that absorb and retain excretory fluids such as urine, and comprise at least one of fibrous material and superabsorbent polymer (hereinafter also referred to as SAP).

[0120] There are no particular restrictions on the use of fibrous materials and superabsorbent polymers as absorbent cores for absorbent articles. Fibrous materials are fibrous materials with liquid absorbency, such as wood pulp fibers, bagasse, kenaf, bamboo, hemp, cotton, and other non-wood pulp fibers, regenerated cellulose fibers such as rayon, semi-synthetic fibers such as acetate fibers, or mixtures thereof. Superabsorbent polymers (SAPs) can be, for example, starch-based, cellulose-based, synthetic polymer-based absorbents, or mixtures thereof. Furthermore, the core-coating sheets 24 and 25 are liquid-permeable sheets, such as nonwoven fabrics and thin cotton paper.

[0121] There exists a situation where the absorbent cores 21-23, from the skin side in the thickness direction, are sequentially referred to as the skin-side layer 21, the intermediate layer 22, and the non-skin-side layer 23. In Figure 4 In the absorbent 20 shown in Figure A, the skin-side layer 21 is not integrally formed with the intermediate layer 22, which is located on the non-skin side of the skin-side layer 21. Instead, it is laminated adjacent to the intermediate layer 22 in the thickness direction through a sheet 26 made of non-woven fabric, thin cotton paper, etc. Furthermore, in Figure 4 In the absorber 20 shown in A, the intermediate layer 22 and the non-skin side layer 23 are integrally formed. That is, the non-skin side layer 23 is not layered on the non-skin side of the intermediate layer 22 through a sheet of non-woven fabric or adhesive HMA, but is directly layered on the non-skin side of the intermediate layer 22.

[0122] The volume fraction of the fibrous material or SAP in the absorbent cores 21-23 can be varied for each absorbent core 21-23 according to its purpose. For example, the volume fraction of SAP may be higher in the skin-side layer 21, higher in the intermediate layer 22, and higher in the non-skin-side layer 23. Furthermore, the skin-side layer 21 may contain only SAP and no fibrous material, the intermediate layer 22 may contain only fibrous material and no SAP, and the non-skin-side layer 23 may contain only SAP and no fibrous material. The absorption rate of SAP is slower than that of fibrous material, so the excretory fluid is easily transferred to the intermediate layer 22 before being absorbed by the SAP in the skin-side layer 21. Furthermore, the excretory fluid absorbed between the fibers of the fibrous material in the intermediate layer 22 gradually transfers to the non-skin-side layer 23 due to gravity, and is firmly absorbed and retained by the SAP in the non-skin-side layer 23.

[0123] Therefore, excrement can be easily introduced into the non-skin side layer 23, and the absorbent cores 21-23 can be effectively utilized in the thickness direction. Consequently, the absorbency retention of the absorbent cores 21-23 is improved, and leakage of excrement can be suppressed even with repeated urination. Furthermore, the dryness of the skin-side surfaces of the absorbent cores 21-23 is ensured, improving the wearing comfort of the diaper 1. Additionally, when excrement in the middle layer 22 and the non-skin side layer 23 attempts to seep back towards the skin side, the SAP in the skin-side layer 21 absorbs and retains the excrement. Therefore, backflow of excrement can be suppressed. Based on this, the dryness of the skin-side surfaces of the absorbent cores 21-23 is also ensured.

[0124] In addition, such as Figure 4 As shown in Figure A, in the thickness direction, sheet 26 is located closer to the skin side (the side where skin-side layer 21 is located) than intermediate layer 22, and adhesive HMA is provided between intermediate layer 22 and sheet 26. Furthermore, adhesive HMA here is a hot-melt adhesive. In other words, adhesive HMA is provided between the fibrous material (intermediate layer 22) and SAP (skin-side layer 21). Furthermore, core-covered sheet 25 is located closer to the non-skin side than non-skin side layer 23, and adhesive HMA is provided between non-skin side layer 23 and core-covered sheet 25. Through the adhesive HMA provided between intermediate layer 22 and sheet 26, and adhesive HMA provided between non-skin side layer 23 and core-covered sheet 25, sheet 26 and core-covered sheet 25 can be bonded, and intermediate layer 22 can be fixed to sheet 26, and non-skin side layer 23 can be fixed to core-covered sheet 25.

[0125] Here, the absorber 20 is not limited to Figure 4 As shown in A. In Figure 4In the absorber 20 shown in Figure A, starting from the skin side in the thickness direction, a sheet (core-covered sheet 24), a skin-side layer 21, a sheet 26, an integrally formed intermediate layer 22 and a non-skin-side layer 23, and a sheet (core-covered sheet 25) are stacked sequentially. However, it is also possible that the sheet 26 is not located between the skin-side layer 21 and the intermediate layer 22, but between the intermediate layer 22 and the non-skin-side layer 23. In this case, it is also possible that the skin-side layer 21 (the layer with a higher volume fraction of SAP) and the intermediate layer 22 (the layer with a higher volume fraction of fibrous material) are formed integrally. That is, it is also possible that the intermediate layer 22 (the layer with a higher volume fraction of fibrous material) is not stacked on the non-skin side of the skin-side layer 21 (the layer with a higher volume fraction of SAP) through a sheet such as non-woven fabric or an adhesive such as HMA, but is directly stacked on the non-skin side of the skin-side layer 21 (the layer with a higher volume fraction of SAP). In this case, the absorbent 20 has a fibrous material containing pulp at a position adjacent to the SAP in the thickness direction. This allows for rapid and temporary absorption of the excretory fluid, suppressing leakage during excretion. Alternatively, the non-skin side layer 23 (the layer with a higher volumetric occupancy of the SAP) may be laminated adjacently in the thickness direction across the sheet 26.

[0126] Furthermore, not limited to the above, the skin-side layer 21, which is not integrally formed with the intermediate layer 22, may be laminated onto the intermediate layer 22 without being separated by a sheet of nonwoven fabric or adhesive HMA. Similarly, the non-skin-side layer 23, which is not integrally formed with the intermediate layer 22, may be laminated onto the intermediate layer 22 without being separated by a sheet of nonwoven fabric or adhesive HMA. Furthermore, the intermediate layer 22 is not limited to being integrally formed with respect to only one of the skin-side layer 21 and the non-skin-side layer 23, but may also be integrally formed with respect to both the skin-side layer 21 and the non-skin-side layer 23. A sheet of nonwoven fabric or adhesive HMA may be provided between the skin-side layer 21 and the intermediate layer 22, and between the intermediate layer 22 and the non-skin-side layer 23, or no sheet of nonwoven fabric or adhesive HMA may be provided between the skin-side layer 21 and the intermediate layer 22, and between the intermediate layer 22 and the non-skin-side layer 23.

[0127] The absorbent core 20 is not limited to the three-layer absorbent core stacking method of skin-side layer 21, middle layer 22, and non-skin-side layer 23. The absorbent core can be stacked in two layers or in only one layer. Hereinafter, the absorbent core used in the form of a single-layer absorbent core in a sheet material such as non-woven fabric (hereinafter referred to as SAP sheet) will be further explained.

[0128] like Figure 4As shown in Figure B, the absorber 20A comprises a substrate sheet 14, a SAP layer 27, and additional sheets 14S. The combination of the substrate sheet 14 and SAP layer 27 with respect to the additional sheets 14S in the absorber 20A can be, for example, the combination of the core-covered sheet 24, skin-side layer 21, and sheet 26 of the absorber 20 described above, or the combination of the core-covered sheet 25, non-skin-side layer 23, and sheet 26 where the sheet 26 is located between the intermediate layer 22 and the non-skin-side layer 23. Here, the SAP layer 27 (the high weight-per-unit area region 211 and the low weight-per-unit area region 212 described later) contains only SAP and does not contain any fibrous material other than SAP. Therefore, a thinner absorber 20A can be formed than an absorber containing fibrous material. The SAP in the SAP layer 27 is fixed to the substrate sheet 14 and the additional sheets 14S using an adhesive HMA. Therefore, the SAP can be reliably fixed to the substrate sheet 14 and the additional sheets 14S.

[0129] In the following description, the term "particle" used with "superabsorbent polymer (SAP)" encompasses any shape or form, including granules, aggregates, flakes, fibers, spheres, and combinations thereof. Furthermore, particles can have any desired shape, such as spherical, polygonal, rod-shaped, polyhedral, or other regular or irregular circular or square forms.

[0130] like Figure 4 As shown in Figure B, SAP layer 27 has a high weight-per-unit-area region 211 where the SAP's weight-per-unit-area is higher than its surroundings. Furthermore, as... Figure 5 As shown, the point S, which represents the maximum thickness in the thickness direction within the high unit area weight region 211, is intermittently located in both the length and width directions. Therefore, Figure 5 The high unit area weight region 211 shown is intermittently arranged in the length and width directions. Furthermore, low unit area weight regions 212, where the SAP has a lower unit area weight than the high unit area weight region 211, are formed between adjacent points S that have the maximum thickness (i.e., around the high unit area weight region 211).

[0131] However, if the points S that constitute the maximum thickness are located discontinuously in the length and width directions, then locally between adjacent points S that constitute the maximum thickness, a region 211 with high weight per unit area can be formed. In other words, locally between adjacent points S that constitute the maximum thickness, a region 211 with high weight per unit area can be connected. Figure 5 In the diagram, a solid line represents the range of the high weight-per-unit-area region 211 when viewed from above, and a dashed line represents the range of the low weight-per-unit-area region 212. Figure 5The ranges of the high unit area weight region 211 and the low unit area weight region 212 are shown schematically for convenience.

[0132] like Figure 4 B and Figure 5 As shown, the low weight-per-unit-area region 212 has a low weight-per-unit-area stacked region 212E with stacked SAP and a non-stacked region 212N without SAP. Here, "without SAP" means not only that SAP particles are absent, but also that the stacked SAP particles are very few, essentially meaning there are no SAP particles at all. Furthermore, in Figure 5 In the diagram, a △ mark is placed at the center of the low unit area weight stacked region 212E, and an × mark is placed at the center of the non-stacked region 212N.

[0133] In the absorbent 20A of this embodiment, the low weight-per-unit area region 212 (low weight-per-unit area layered region 212E and non-layered region 212N) serves as the bending starting point, easily deforming along the contours of the wearer's body, thus improving fit. Furthermore, the low weight-per-unit area region 212, which serves as the bending starting point, includes the low weight-per-unit area layered region 212E, which is capable of absorbing and retaining excrement, and the non-layered region 212N, which is easier to bend due to the absence of SAP. Thus, even in the low weight-per-unit area region 212, where the SAP weight-per-unit area is lower than that of the high weight-per-unit area region 211, both ease of deformation along the contours of the wearer's body and the ability to absorb and retain excrement are balanced.

[0134] As described above, the low unit area weight region 212 is formed between points S, which are discontinuously arranged in the length and width directions and have the maximum thickness. Therefore, as Figure 5 As shown, the low weight-per-unit area region 212 is also intermittently arranged in the length and width directions. That is, the low weight-per-unit area layered region 212E is intermittently arranged in the length and width directions, and similarly, the non-layered region 212N is also intermittently arranged in the length and width directions. For the absorber 20A, by sparsely arranging the low weight-per-unit area layered region 212E and the non-layered region 212N on the plane, it is possible to have an expandable deformability along the contours of the wearer's body and an absorbent retention capacity for excretions on the plane.

[0135] In the absorber 20A of this embodiment, for example, in Figure 5In the top view shown, the number of low-weight-per-unit-area laminated regions 212E varies in each of the regions that divide the absorber 20A into three equal parts along its length. Similarly, the number of non-laminated regions 212N also varies in each of the regions that divide the absorber 20A into three equal parts along its length. Although details will be described later, when SAP particles are supplied to the substrate sheet to manufacture the absorber, the areas where SAP particles do not adhere become the non-laminated regions 212N, and the areas where some SAP particles adhere become the low-weight-per-unit-area laminated regions 212E. The non-laminated regions 212N and the low-weight-per-unit-area laminated regions 212E are irregularly generated on the plane; therefore, as described above, when viewed from above, the number of low-weight-per-unit-area laminated regions 212E and the number of non-laminated regions 212N vary in each of the regions that divide the absorber 20A into three equal parts along its length. In this way, by irregularly arranging the low-weight-per-unit-area-area-layered regions 212E and the non-layered regions 212N on a plane, the absorbent body 20A can easily deform along the contours of the wearer's body, thereby improving fit.

[0136] Furthermore, in the absorbent 20A of this embodiment, by having a low weight-per-area region 212 surrounding the high weight-per-area region 211, the excrement can easily diffuse in the planar direction. Assuming the weight-per-area of ​​the SAP is constant in the plane, there is a possibility that adjacent SAPs may adhere together and clump together when absorbing moisture, hindering further diffusion of the excrement. In other words, when the weight-per-area of ​​the SAP is constant in the plane, there is a concern about so-called gel blockage.

[0137] Therefore, in the absorber 20A of this embodiment, by having a low unit area weight region 212 around the high unit area weight region 211, the excrement can easily diffuse along the low unit area weight region 212 even after absorbing a certain amount of excrement, thus suppressing the occurrence of the above-mentioned gel blockage.

[0138] The non-stacked regions 212N are arranged such that, when viewed from a high unit area weight region 211, there are more points on the width side than on the length side. In other words, the number of points S that are adjacent to the non-stacked regions 212N on one or the other side of the width direction among the points S that become the maximum thickness is greater than the number of points S that are adjacent to the non-stacked regions 212N on one or the other side of the length direction. As a result, the low unit area weight stacked regions 212E are arranged such that, when viewed from the high unit area weight region 211, there are more points on the length side than on the width side. In this case, when the absorbent 20A has absorbed the excretion liquid, that is, in the swollen state, more SAPs adhere to each other in the length direction where the low unit area weight stacked regions 212E are more concentrated. Therefore, it is possible to prevent the absorbent 20A from losing its flexibility in the width direction in the swollen state.

[0139] It could also be, in Figure 5 The absorber 20A shown also includes the following (described later) Figure 8 The groove region 215 is shown. A detailed explanation of the groove region 215 will be given later, but by having the absorbent body 20A have the groove region 215, for example, when it is sandwiched between the wearer's legs (i.e., the groin area) during wear, the crotch area is more easily deformed in the width direction, enhancing the tummy area's containment and further improving the fit. In this case, the groove region 215 itself becomes a bending point, thus contributing to improved fit. However, the groove region 215 may not be provided in the absorbent body 20A.

[0140] Furthermore, in the absorber 20A of this embodiment, it is preferable that, as in Figure 4 As shown in Figure B, the maximum thickness T is 3 mm or less, and the spacing between adjacent points S that constitute the maximum thickness is less than 5 times the maximum thickness T. This allows for the arrangement of a large number of high weight-per-unit area regions and a large number of low weight-per-unit area regions while maintaining the thinness of the absorbent body 20A. Therefore, in the absorbent body 20A with the highly absorbent polymer, the fit during wear can be improved while maintaining thinness. Furthermore, it is even more preferable that the maximum thickness T is 2 mm or less, and the spacing between adjacent points S that constitute the maximum thickness is less than 4 times the maximum thickness T. This further improves the fit during wear in the absorbent body 20A with the highly absorbent polymer while maintaining thinness.

[0141] Preferably, in Figure 5In the top view shown, the diameter of the circumscribed circle CC, which is circumscribed by each of the multiple high weight-per-unit area regions 211, is 2 mm or more and 4 mm or less. This allows for a reduction in the size of each of the multiple high weight-per-unit area regions 211, enabling the arrangement of a large number of high weight-per-unit area regions 211 and a large number of low weight-per-unit area regions 212 on the substrate sheet 14. Consequently, the absorber 20A can easily deform along the contours of the wearer's body, improving fit.

[0142] Furthermore, it is preferable that, in Figure 5 In the top view shown, the largest diameter among the diameters of the inscribed circles IC that are internally tangent to the multiple non-stacked regions 212N is less than or equal to the maximum thickness T. Thus, by reducing the size of the non-stacked regions 212N without SAP when viewed from above, leakage of the drain fluid through the non-stacked regions 212N can be suppressed.

[0143] Furthermore, in Figure 5 In the top view shown, a joint 213 is provided on the outer side of the region where the SAP (i.e., the high weight-per-unit area region 211 and the low weight-per-unit area region 212) in the length direction. The joint 213 is a portion formed by joining the substrate sheet 14 and another sheet 14S together in the thickness direction. The joint 213 is formed by known joining methods such as embossing, welding, and bonding. As a result, an opening between the substrate sheet 14 and the other sheet 14S can be suppressed.

[0144] Furthermore, the area in the substrate sheet 14 where the joint 213 is formed is an area without SAP and an area without adhesive for fixing SAP. Here, an area without SAP refers to an area where SAP is not substantially disposed (e.g., an area where the weight of SAP disposed in the entire substrate sheet 14 is less than 10%). Alternatively, the joint 213 may not be provided.

[0145] Figure 6 A is a cross-sectional schematic diagram showing the case where 14 layers of highly absorbent polymer are stacked on a substrate sheet. Figure 6 B is a top view showing the recessed area 214F on one side of the substrate sheet 14.

[0146] In this embodiment, such as Figure 6As shown in Figure A, recessed regions 214 are formed on one side and the other side of the substrate sheet 14 in the thickness direction. Specifically, a recessed region 214F is formed on one side of the substrate sheet 14, and a recessed region 214B is formed on the other side of the substrate sheet 14. On one side of the substrate sheet 14 in the thickness direction, a larger amount of SAP is disposed in the recessed region 214F, forming a high weight-per-unit area region 211. On the other hand, in the regions other than the recessed region 214F, no SAP is disposed, or even if SAP is disposed, it is disposed in fewer amounts than in the recessed region 214F, thereby forming a low weight-per-unit area region 212 (low weight-per-unit area laminated region 212E or non-laminated region 212N).

[0147] In addition, such as Figure 6 As shown in Figure B, on one side of the substrate sheet 14, the recessed region 214F is intermittently arranged in the length and width directions. Consequently, the high weight-per-unit area region 211 is arranged such that the point S, which represents the maximum thickness in the thickness direction, is intermittently positioned in the length and width directions. Similarly, the low weight-per-unit area regions 212 (low weight-per-unit area laminated region 212E and non-laminated region 212N) are also intermittently arranged in the length and width directions.

[0148] Furthermore, the difference SB1 between the highest point H1 and the lowest point L1 in the thickness direction on one side of the substrate sheet 14 is different from the difference SB2 between the highest point H2 and the lowest point L2 in the thickness direction on the other side of the substrate sheet 14. In other words, the depth of the recessed region 214 where the SAP is disposed can be different in the recessed region 214F on one side of the substrate sheet 14 and the recessed region 214B on the other side. That is, in Figure 6 In the substrate sheet 14 shown in B, the recessed region 214F on one side is formed with a shallower recess, while the recessed region 214B on the other side is formed with a deeper recess.

[0149] Here, in Figure 6 In the substrate sheet 14 shown in Figure A, the absorber 20A is formed by arranging SAP in the recessed region 214F on the shallower side of the recess. However, the absorber 20A can also be formed by arranging SAP in the recessed region 214B on the deeper side of the recess. For example, by arranging more SAP in the recessed region 214B on the deeper side of the recess compared to the recessed region 214F on the shallower side of the recess, the absorption and retention capacity of the drained liquid can be improved. Conversely, by arranging SAP in the recessed region 214F on the shallower side of the recess, the liquid diffusivity can be improved compared to the recessed region 214B. Therefore, by making the depths different in the recessed regions 214F and 214B as described above, it is possible to select which recessed region 214 to arrange SAP in, and an absorber with properties corresponding to the purpose can be formed.

[0150] However, it is also possible that the difference SB1 between the highest point H1 and the lowest point L1 in the thickness direction on the front side of the substrate sheet 14 is equal to the difference SB2 between the highest point H2 and the lowest point L2 in the thickness direction on the back side of the substrate sheet 14. That is, it is also possible that the depth of the recessed region 214 where the SAP is configured is the same on one side and the other side of the substrate sheet 14.

[0151] like Figure 6 As shown in Figure A, on the front side of the substrate sheet 14, the weight of the SAP stacked below the highest point H1 is more than 50% of the total weight of the SAP stacked on the substrate sheet 14. Therefore, by stacking the desired weight of the SAP in the recessed area of ​​the substrate sheet 14, a high weight-per-unit-area region 211 can be formed at an appropriate location.

[0152] In addition, Figure 6 In the top view shown in B, the largest diameter among the diameters of the inscribed circles IC that are internally tangent to the multiple non-stacked regions 212N is less than or equal to the difference SB1 on the front side. Therefore, by reducing the size of the non-stacked regions 212N without SAP when viewed from above, leakage of the drain fluid through the non-stacked regions 212N can be suppressed.

[0153] Here, in Figure 6 In the top view shown in B, the ratio will be... Figure 6 The area below the midpoint M1 between the highest point H1 and the lowest point L1 shown in Figure A is defined as the range of the recessed region 214F. In this case, it is preferable that the total length LG1 of the plurality of recessed regions 214F along the imaginary line V1 passing through the center C of the plurality of recessed regions 214F in the longitudinal direction is more than 50% of the overall length of the substrate sheet 14. Thus, by laminating SAP onto the desired area of ​​the substrate sheet 14, a high weight-per-unit area region 211 and a low weight-per-unit area region 212 can be formed in appropriate locations.

[0154] Furthermore, it is also preferable that the total length LG2 of the plurality of recessed regions 214F along the imaginary line V2 passing through the center of the plurality of recessed regions 214F in the width direction is 50% or more of the overall length of the substrate sheet 14. Thus, by laminating SAP onto the desired area of ​​the substrate sheet 14, it is possible to form a high weight-per-unit area region 211 and a low weight-per-unit area region 212 in appropriate locations.

[0155] Figure 7 A is a cross-sectional schematic diagram showing the state of absorber 20A before it absorbs moisture. Figure 7 B is a cross-sectional schematic diagram showing the state of absorber 20A after absorbing water.

[0156] In the absorbent 20A of this embodiment, there are joining regions 28 where the substrate sheet 14 and the other sheet 14S are joined together between adjacent points S that are at their maximum thickness, and non-jointing regions 29 where the substrate sheet 14 and the other sheet 14S are not joined together between adjacent points S that are at their maximum thickness. Thus, by having joining regions 28 that serve as bending points and non-jointing regions 29 where SAP can be disposed between the substrate sheet 14 and the other sheet 14S, it is possible to balance the ease of deformation along the contours of the wearer's body with the absorption and retention of excrement.

[0157] In the bonding region 28, and in the non-laminated region 212N, the substrate sheet 14 and the additional sheet 14S are bonded together via an adhesive HMA. Furthermore, when the absorbent 20A absorbs moisture, as... Figure 7 As shown in Figure B, the SAP swells, and the bonding portion of the bonding area 28 between the substrate sheet 14 and the other sheet 14S separates. In this way, the bonding portion of the bonding area 28 separates as the absorbent 20A absorbs moisture, thereby preventing the SAP swelling from being hindered by the bonding area 28.

[0158] Figure 8 This is a top view schematic diagram of the absorber 20B of the modified example.

[0159] The modified absorber 20B has a channel region 215 where the weight per unit area of ​​SAP is lower than that of the high weight per unit area region 211. For example... Figure 8 As shown, the groove region 215 extends along the length direction, and in the width direction, the width of the groove region 215 is greater than the interval between adjacent points S that are the points of maximum thickness. That is, the width of the groove region 215 is greater than the width of the low unit area weight region 212 formed between adjacent high unit area weight regions 211 (i.e., around the high unit area weight region 211). For the modified absorbent 20B, for example, when sandwiched between the wearer's legs (i.e., in the groin area) during wear, the groove region 215 becomes a bending starting point, easily deforming along the width direction at the wearer's crotch, enhancing the crotch area's containment capacity and further improving the fit. Additionally, excretory fluid easily diffuses in the length direction.

[0160] The channel region 215 has multiple sections in the width direction. Specifically, as follows: Figure 8 As shown, two groove areas 215 are provided. This further enhances the storage capacity at the crotch and improves the fit. However, it is also possible that only one groove area 215 is provided in the width direction.

[0161] ===Absorbent Manufacturing Apparatus and Method for Manufacturing Absorbents===

[0162] The following describes the absorber manufacturing apparatus and the method for manufacturing the absorber, as described above, regarding the absorber 20A.

[0163] <<Structure of Absorber Manufacturing Apparatus 50>>

[0164] Figure 9 This is a schematic diagram showing the outline of the absorber manufacturing apparatus 50.

[0165] The absorbent manufacturing apparatus 50 is an apparatus for manufacturing absorbents containing superabsorbent polymer (SAP). The absorbent manufacturing apparatus 50 includes a conveying section 11x, an upstream adhesive coating section 18, a particle supply section 19, a suction section 11P, an adhesive discharge section 15D, and a joint forming section 11em.

[0166] The conveying unit 11x is a component that conveys the substrate sheet 14 along the conveying direction. Figure 9 In the absorber manufacturing apparatus 50 shown, the conveying section 11x includes a conveyor belt 11cn and a plurality of conveying rollers 11rn. The upper surface of the conveyor belt 11cn, which is a driven, circular belt, is designated as the conveying surface of the substrate sheet 14. That is, the conveyor belt 11cn conveys the substrate sheet 14 while supporting the lower surface of the substrate sheet 14 (hereinafter referred to as "one surface"). Therefore, the conveyor belt 11cn may be referred to as a support section.

[0167] In addition, Figure 9 In the absorbent manufacturing apparatus 50 shown, the conveying unit 11x is an adsorption belt conveyor that conveys the substrate sheet 14 by suction using the suction unit 11P through multiple openings 11pn (described later) provided on the conveying surface of the conveyor belt 11cn. The conveying roller 11rn can be a drive roller that is driven to rotate by a drive source such as an electric motor, or it can be a driven roller that rotates passively without a drive source.

[0168] The upstream adhesive coating section 18 is a component that pre-coats the substrate sheet 14 with adhesive before supplying SAP particles 19S to the substrate sheet 14. For example... Figure 9 As shown, the upstream adhesive coating section 18 is located upstream of the particle supply section 19 that supplies SAP particles 19S in the conveying direction. Here, the adhesive applied to the upstream adhesive coating section 18 is a hot-melt adhesive. Before supplying the SAP particles 19S to the substrate sheet 14 using the particle supply section 19, the adhesive is pre-applied to the substrate sheet 14, thereby facilitating the adhesion of the SAP particles 19S to the substrate sheet 14 and reducing the amount of SAP particles 19S rebound. This prevents the SAP particles 19S from being positioned unexpectedly. However, it is also possible for the absorber manufacturing apparatus 50 to not have the upstream adhesive coating section 18.

[0169] The particle supply unit 19 is a component that supplies SAP particles 19S to the upper surface of the substrate sheet 14 (hereinafter referred to as the "other side"). When the particle supply unit 19 releases SAP particles 19S, the SAP particles 19S are supplied to the substrate sheet 14 disposed on the conveying surface of the conveying unit 11x due to gravity, or are discharged together with pressurized air to the substrate sheet 14 disposed on the conveying surface of the conveying unit 11x.

[0170] The suction unit 11P is a component that sucks the substrate sheet 14 from one side (lower surface) of the substrate sheet 14 through multiple openings 11pn of the conveyor belt 11cn. Details about the suction unit 11P will be described later.

[0171] The adhesive discharge section 15D is a component that discharges adhesive along with airflow toward the substrate sheet 14. The adhesive discharge section 15D is located downstream of the particle supply section 19 in the conveying direction. Furthermore, in Figure 9 In the absorbent manufacturing apparatus 50 shown, the adhesive discharge section 15D has two adhesive discharge sections 15D: a first adhesive discharge section 15x1 and a second adhesive discharge section 15x2 disposed downstream of the first adhesive discharge section 15x1 in the conveying direction. Details regarding the adhesive discharge sections 15D will be described later.

[0172] The joint forming portion 11em is a component formed by joining the substrate sheet 14 and the other sheet 14S in the thickness direction after they are joined together. Regarding the joint forming portion 11em, for the substrate sheet 14 and the other sheet 14S, other known joining methods can be used, such as embossing, welding, or bonding. The joint forming portion 11em can be used to form the aforementioned... Figure 5 The junction 213 in the absorber 20A shown.

[0173] In this embodiment, the absorbent containing the highly absorbent polymer described above can be manufactured using the absorbent manufacturing apparatus 50 having each of the above structures. As a method for manufacturing an absorbent containing the highly absorbent polymer, it first includes at least: a conveying step in which the substrate sheet 14 is conveyed while one side (lower surface) is supported by a support (conveyor belt 11cn); and a particle supply step in which SAP particles 19S are supplied toward the other side (upper surface) of the substrate sheet 14. Thus, an absorbent having a highly absorbent polymer laminated on the substrate sheet 14 can be manufactured.

[0174] In this embodiment, as a method for manufacturing an absorbent containing a highly absorbent polymer, adhesive may be applied to the other side (upper surface) of the substrate 14 using an upstream adhesive coating section 18 at a location upstream of the position where the SAP particles 19S are supplied to the substrate 14 in the transport direction (upstream adhesive coating step). This allows the SAP particles 19S to be easily adhered to the substrate 14. However, as a method for manufacturing an absorbent containing a highly absorbent polymer, the upstream adhesive coating step may not be included.

[0175] In addition, as a method for manufacturing an absorbent containing a highly absorbent polymer, in this embodiment, another sheet 14S may be supplied downstream of the position where the SAP particles 19S are supplied to the substrate sheet 14 in the transport direction of the substrate sheet 14, in a manner that covers the SAP particles 19S from the other side (upper surface) of the substrate sheet 14 (an additional sheet supply step). Furthermore, in this embodiment, the additional sheet 14S and the substrate sheet 14 may be joined in the thickness direction along a cross direction that intersects the transport direction of the substrate sheet 14 in the area on the other side (upper surface) of the substrate sheet 14 where no adhesive is applied (a joint forming step). This can suppress openings between the substrate sheet 14 and the additional sheet 14S. However, as a method for manufacturing an absorbent containing a highly absorbent polymer, the additional sheet supply step and the joint forming step may not be included.

[0176] In this embodiment, the absorbent is formed by cutting it to the desired size further downstream of the joint forming process. Furthermore, in this embodiment, an additional sheet 14S is laminated after SAP particles are supplied to the substrate sheet 14, but this is not a limitation. For example, after laminating SAP particles to the substrate sheet 14, the absorbent can also be formed simply by cutting the substrate sheet 14 to the desired size. Alternatively, the absorbent can be formed by laminating a fibrous material containing pulp after laminating SAP particles to the substrate sheet 14. Thus, it is easy to manufacture an absorbent capable of rapidly and temporarily absorbing excrement and suppressing overflow and leakage of excrement during discharge. Furthermore, if the absorbent is made from a fibrous material containing pulp mixed in addition to SAP particles, such fibrous material can be supplied to the substrate sheet 14 before or after the SAP particles 19S are supplied to the particle supply section 19.

[0177] As described above, the conveying section 11x of the absorbent manufacturing apparatus 50 is an adsorption belt conveyor that conveys the substrate sheet 14 by suction via a suction section 11P through multiple openings 11pn provided on the conveying surface of the conveyor belt 11cn. Details of the suction section 11P and the conveyor belt 11cn will be explained in this regard.

[0178] Figure 10 This is a diagram illustrating the suction opening 11su of the suction section 11P. Figure 11 A is a partial cross-sectional view of the conveyor belt 11 cm. Figure 11 B is a partial top view schematic diagram showing the conveyor belt 11 cm. Furthermore, in Figure 10 and Figure 11 In A, the outline of the substrate sheet 14 is represented by dashed lines for reference.

[0179] like Figure 10 As shown, the suction unit 11P is located on the side opposite to the side where the substrate sheet 14 is located when viewed from the conveyor belt 11cn (support portion). Furthermore, a suction opening 11su is provided on the side of the suction unit 11P where the substrate sheet 14 is located. The suction unit 11P performs suction through the suction opening 11su. Additionally, when viewed from the suction opening 11su of the suction unit 11P, the conveyor belt 11cn is located between the suction opening 11su and the substrate sheet 14, and the conveyor belt 11cn conveys the substrate sheet 14 in the conveying direction.

[0180] The conveyor belt 11cn is, for example, a mesh belt, and multiple openings 11pn are provided on the conveying surface 11m of the conveyor belt 11cn. Specifically, such as... Figure 11 A and Figure 11 As shown in Figure B, the conveyor surface 11m of the conveyor belt 11cn is formed by weaving a linear member made of fibers from synthetic resins such as nylon. However, the linear member can also be made of metal such as metal wire. This linear member is, for example, composed of a longitudinal member 116 and a transverse member 117, and the opening defined by the longitudinal member 116 and the transverse member 117 becomes the opening 11pn for suction of the substrate sheet 14.

[0181] In the aforementioned particle supply process, such as Figure 11 As shown in Figure A, the suction unit 11P draws the substrate sheet 14 from one side (lower surface) through multiple openings 11pn provided on the conveyor surface 11m of the conveyor belt 11cn. The substrate sheet 14, as described above, is formed of a very soft and easily deformable material such as non-woven fabric; therefore, the suction force generated by the suction unit 11P (refer to...) Figure 11 The hollow arrow of A is used to pull the part corresponding to the opening 11pn, so that the concave region 214 is formed in a manner corresponding to the shape of the opening 11pn.

[0182] At this time, the supplied SAP particles 19S (in) Figure 11 (Not shown in Figure A) It also easily remains in the recessed region 214 of the substrate sheet 14 due to the suction force generated by the suction section 11P. Therefore, compared with the above... Figure 6Similarly, as described in A, a greater number of SAP particles 19S are arranged in the concave region 214, forming a high weight-per-unit-area region 211. On the other hand, in the region outside the concave region 214 ( Figure 11 In region A (which is blocked by longitudinal member 116 and does not become recessed region 214), SAP particles 19S are not configured, or even if SAP particles 19S are configured, they are configured in fewer quantities than in recessed region 214. As a result, a low weight per unit area region 212 (low weight per unit area stacked region 212E or non-stacked region 212N) is formed.

[0183] Based on the above, in the conveying section 11x of the absorber manufacturing apparatus 50, the support section (conveyor belt 11cn) has a plurality of openings 11pn. In the particle supply process, the substrate sheet 14 is drawn from one side (lower surface) of the substrate sheet 14 through the plurality of openings 11pn. As a result, absorbers forming a high unit area weight region 211 and a low unit area weight region 212 surrounding each high unit area weight region 211 can be manufactured.

[0184] In addition, such as Figure 11 As shown in Figure B, the diameter of the inscribed circle IC, which is tangent to the opening 11pn of the conveyor belt 11cn, is greater than or equal to the average particle size of the SAP particles. For example, preferably, the diameter of the inscribed circle IC, which is tangent to the opening 11pn of the conveyor belt 11cn, is 2 mm or more and 4 mm or less. Therefore, by reducing the size of each of the multiple high weight-per-unit area regions 211 when viewed from above, a large number of high weight-per-unit area regions 211 and a large number of low weight-per-unit area regions 212 can be arranged on the substrate sheet 14. In this embodiment, an absorbent material with SAP that maintains thinness while providing good fit when worn can be easily manufactured.

[0185] Furthermore, it is preferable that the opening ratio of the openings 11pn in the support portion (conveyor belt 11cn) is 40% or more and 60% or less. This allows for the appropriate formation of a high weight-per-unit-area region 211 within the absorber. In the following description, the opening ratio refers to the proportion of the area of ​​the opening per unit area.

[0186] Figure 12 This is a top view schematic diagram showing another example of the suction opening su of the suction section 11P. Furthermore, in Figure 12 Similarly, for reference, the outline of the substrate sheet 14 is indicated by a dashed line at the end 142 of the intersection direction with the substrate sheet 14. Additionally, a single-dotted line indicates the position of the particle supply section 19 when viewed from above.

[0187] In the particle supply process, the suction unit 11P draws particles from one side (lower surface) of the substrate sheet 14 via... Figure 12The suction opening su (first opening region 111 and second opening region 112 described later) and the opening 11pn of the conveyor belt 11cn are used to suction the substrate sheet 14, thereby forming the aforementioned... Figure 8 The absorber 20B shown has a channel region 215. Hereinafter, the characteristics of the suction opening su of the suction section 11P will be described.

[0188] The suction opening su of the suction section 11P has a first opening region 111 and a second opening region 112. For example... Figure 12 As shown, the second opening region 112 is adjacent to the first opening region 111 in the intersecting direction with the transport direction of the substrate sheet 14. Furthermore, the second opening region 112 may have multiple opening regions (two in this case) in the intersecting direction. However, there may also be only one second opening region 112.

[0189] Here, the opening ratio of the first opening region 111 is greater than or equal to the opening ratio of the opening 11pn in the region of the conveyor belt 11cn (support portion) where the opening 11pn is provided. For example, in the above-described... Figure 11 In the conveyor belt 11cn shown in Figure B, the opening 11pn is defined by the longitudinal member 116 and the transverse member 117. In this case, considering the entire area of ​​the conveyor belt 11cn where the opening 11pn is provided, the opening ratio of the opening 11pn reduces the amount of the size (width) of the longitudinal member 116 and the transverse member 117. In contrast, in the first opening region 111, the entire region becomes an opening (space). However, although not shown, a transverse strip may be provided at the edge of the opening in the first opening region 111. This reduces the suction force that can suppress the degree of shape collapse of the substrate sheet 14.

[0190] Furthermore, the opening ratio of the second opening region 112 is lower than that of the first opening region 111, and is lower than the opening ratio of the opening 11pn in the region of the conveyor belt 11cn (support portion) where the opening 11pn is located. Specifically, it is preferable that the opening ratio of the second opening region 112 is 25% or more and 35% or less. However, as long as the opening ratio of the second opening region 112 is lower than that of the first opening region 111, and is lower than the opening ratio of the opening 11pn in the region of the conveyor belt 11cn (support portion) where the opening 11pn is located, it can be in a range other than 25% or more and 35% or less.

[0191] As described above, in the particle supply process, the particle supply unit 19 supplies SAP particles 19S to the other side (upper surface) of the substrate sheet 14, and the suction unit 11P suctions the substrate sheet 14 from one side (lower surface) via the first opening region 111 and the second opening region 112, and the opening 11pn of the conveyor belt 11cn. Here, as described above, the opening ratio of the second opening region 112 is lower than that of the first opening region 111. Therefore, when viewed from above, the suction force of the area of ​​the substrate sheet 14 that is suctioned via the second opening region 112 is lower than the suction force of the area of ​​the substrate sheet 14 that is suctioned via the first opening region 111. At this time, for the SAP particles 19S supplied to the substrate sheet 14 (in Figure 12 (Not shown in the figure) Compared to the area of ​​the substrate 14 that is drawn in through the first opening region 111, it is easier to stay in the area of ​​the substrate 14 that is drawn in through the second opening region 112.

[0192] Furthermore, as described above, the opening ratio of the second opening region 112 is less than the opening ratio of the opening 11pn in the region of the conveyor belt 11cn where the opening 11pn is provided. Therefore, in the region where the substrate sheet 14 is drawn through the second opening region 112, the suction force is reduced due to the second opening region 112. Thus, in the region where the substrate sheet 14 is drawn through the second opening region 112, the suction force to the extent that the portion of the substrate sheet 14 corresponding to the opening 11pn is pulled and forms a recessed region 214 can be suppressed. Therefore, in the region where the substrate sheet 14 is drawn through the second opening region 112, the formation of a high unit area weight region 211 can be suppressed, and a channel region 215 with a lower unit area weight of SAP than the high unit area weight region 211 can be formed. In addition, as described above, there are two second opening regions 112 in the intersecting direction, so as Figure 8 As shown in the absorber 20B, two channel regions 215 are formed, each corresponding to one of the two second opening regions 112.

[0193] On the other hand, the opening ratio of the first opening region 111 is greater than or equal to the opening ratio of the opening 11pn in the region of the conveyor belt 11cn where the opening 11pn is provided. Therefore, in the region of the substrate sheet 14 that is drawn through the first opening region 111, the suction force is not reduced by the first opening region 111, and a recessed region 214 can be formed, which is easily retained in the recessed region 214 of the substrate sheet 14 by the suction force generated by the suction part 11P. That is, in the region that is drawn through the first opening region 111, a high unit area weight region 211 and a low unit area weight region 212 are formed.

[0194] Furthermore, the suction opening su of the suction section 11P has a third opening region 113 and a non-opening region 114. For example... Figure 12As shown, the third opening region 113 is located downstream of the first opening region 111 in the conveying direction and has a portion overlapping the first opening region 111 in the crossing direction. Similarly, the non-opening region 114 is located downstream of the second opening region 112 in the conveying direction and also has a portion overlapping the second opening region 112 in the crossing direction. The opening ratio of the third opening region 113 is lower than that of the first opening region 111. However, the third opening region 113 may also be located upstream of the first opening region 111 in the conveying direction, and the non-opening region 114 may also be located upstream of the second opening region 112 in the conveying direction. Alternatively, the suction opening su of the suction section 11P may not have the third opening region 113 or the non-opening region 114.

[0195] In the particle supply process, suction force continues to be generated in the third opening region 113, which is downstream of the first opening region 111, and suction force can be suppressed in the non-opening region 114, which is downstream of the second opening region 112. This prevents SAP particles that bounce back in the region of the substrate sheet 14 where SAP particles are supplied, i.e., in the region of the substrate sheet 14 where they are sucked through the first opening region 111 and the second opening region 112, from being disposed in the channel region 215 on the downstream side.

[0196] Furthermore, the suction opening su of the suction section 11P has a fourth opening region 115. The fourth opening region 115 is located, when viewed from above, on the outer side of the first opening region 111 and the third opening region 113 in the intersecting direction, and overlaps with the end of the substrate sheet 14 in the intersecting direction. During the transport process, the suction section 11P suctions the end of the substrate sheet 14 from one side (lower surface) of the substrate sheet 14 via the fourth opening region 115. This helps to prevent the substrate sheet 14 from rolling up during transport. However, it is also possible for the suction opening su of the suction section 11P not to have a fourth opening region 115.

[0197] Figure 13 This diagram illustrates the supply of SAP particles and the discharge of adhesive in the absorbent manufacturing apparatus 50.

[0198] In the absorber manufacturing apparatus 50 of this embodiment, immediately after the process of supplying SAP particles from the particle supply unit 19 (particle supply process), the adhesive discharge unit 15D (first adhesive discharge unit 15x1) discharges adhesive 15H along with an airflow toward the substrate sheet 14 (downstream adhesive discharge process). Here, the adhesive 15H is a hot melt adhesive, which is discharged from a plurality of discharge ports (nozzles) (not shown) provided by the adhesive discharge unit 15D. Then, after the adhesive 15H is discharged from the first adhesive discharge unit 15x1, the adhesive 15H is further discharged along with an airflow toward the substrate sheet 14 by a second adhesive discharge unit 15x2 provided downstream of the first adhesive discharge unit 15x1 in the conveying direction.

[0199] Furthermore, the adhesive 15H is discharged along with the airflow, and in this embodiment, the pressure of the airflow is the same in both the first adhesive discharge section 15x1 and the second adhesive discharge section 15x2. However, this is not a limitation, and different air pressures may be used for each section.

[0200] SAP particles 19S supplied from particle supply unit 19 easily bounce back when they hit substrate sheet 14 on conveyor surface 11m (see reference). Figure 13 In this embodiment, it is envisioned that approximately 60% of the supplied SAP particles 19S will bounce back. However, there is a concern that the supplied SAP particles 19S may bounce back in unexpected directions and thus scatter to locations where they should not be placed.

[0201] Regarding this point, in the absorber manufacturing apparatus 50 of this embodiment, as... Figure 13 As shown, the adhesive 15H discharged from the adhesive discharge section 15D can be used to push back at least a portion of the SAP particles 19S that have bounced back from the substrate sheet 14 toward the substrate sheet 14 side. Here, "pushing back" means causing the SAP particles 19S to move in the opposite direction to the conveying direction and in the direction of gravity (vertically downward). In other words, when the discharged adhesive 15H encounters the SAP particles 19S that bounced back from the substrate sheet 14, the SAP particles 19S can be caused to fall back toward the substrate sheet 14 side. Furthermore, the airflow discharged along with the adhesive 15H can reduce the possibility of the SAP particles 19S being positioned unexpectedly. Moreover, by wrapping the adhesive 15H around the bounced SAP particles 19S, the SAP particles 19S can be more reliably fixed relative to the substrate sheet 14.

[0202] Furthermore, in this embodiment, adhesive 15H is discharged not only from the first adhesive discharge section 15x1, but also from the second adhesive discharge section 15x2, which is located downstream of the first adhesive discharge section 15x1 in the conveying direction. Therefore, by utilizing the adhesive 15H discharged from the second adhesive discharge section 15x2 to push back the SAP particles 19S, which cannot be completely pushed back by the adhesive 15H discharged from the first adhesive discharge section 15x1 alone, towards the substrate sheet 14, the amount of rebound can be further reduced. This allows for more reliable fixation of the SAP particles 19S relative to the substrate sheet 14.

[0203] Furthermore, the absorbent manufacturing apparatus 50 of this embodiment has two adhesive discharge sections 15D (first adhesive discharge section 15x1 and second adhesive discharge section 15x2), but is not limited to this. For example, when the amount of supplied SAP particles 19S is small, there may only be a first adhesive discharge section 15x1. In addition, the first adhesive discharge section 15x1 and the second adhesive discharge section 15x2 can push back the rebounding SAP particles 19S, but the first adhesive discharge section 15x1 can focus on fixing the SAP particles 19S to the substrate sheet 14, while the second adhesive discharge section 15x2 can be designed with the main purpose of improving the bonding strength of the materials (substrate sheet 14, etc.) and adjusting the strength.

[0204] Furthermore, in this embodiment, separating the first adhesive discharge section 15x1 and the second adhesive discharge section 15x2 increases the degree of freedom of each adhesive discharge section 15D. However, the first adhesive discharge section 15x1 and the second adhesive discharge section 15x2 can also be an integral adhesive discharge section. When the first adhesive discharge section 15x1 and the second adhesive discharge section 15x2 are integrated, costs can be reduced compared to installing separate devices, and the maintenance and management of the device also become easier.

[0205] As described above, since the SAP particles 19S tend to bounce back when supplied from the particle supply unit 19, in this embodiment, ... Figure 13 As shown, the conveyor surface 11m of the conveyor belt 11cn is inclined relative to the horizontal plane Hr in a manner that descends downstream in the conveying direction. In this way, the SAP particles 19S that bounce off the substrate sheet 14 are more likely to move downstream due to gravity, which can reduce the configuration of SAP particles 19S in unexpected positions.

[0206] Furthermore, in the case of Figure 13When the angle of inclination of the conveyor surface 11m relative to the horizontal plane Hr is set to θ0, the inclination angle θ0 in this embodiment is approximately 30 degrees. This is because the rest angle of SAP particles (the maximum angle at which the inclined plane remains stable without collapsing when accumulating particles) is 32 to 38 degrees, so the inclination angle is set near this angle. By setting the inclination angle θ0 to approximately 30 degrees, it is possible to prevent the SAP particles 19S discharged from the particle supply section 19 from rolling after being carried on the substrate sheet 14, and compared to the case where they are discharged to the conveyor surface parallel to the horizontal plane, the SAP particles 19S are less likely to bounce back. When the conveyor surface 11m of the conveyor belt 11cn is inclined in such a way that the downstream side is lowered, the inclination angle θ0 can be set to approximately 75 degrees.

[0207] Furthermore, it is preferable that the conveying surface 11m is inclined relative to the horizontal plane Hr in a manner that descends downstream in the conveying direction, as described above, but this is not a limitation. For example, the conveying surface 11m may be horizontal, or it may be inclined relative to the horizontal plane Hr in a manner that descends upstream in the conveying direction. It may also be inclined in a manner that descends upstream in the conveying direction (that is, in a manner that rises downstream). In the absorbent manufacturing apparatus 50 of this embodiment, since the conveyor belt 11cn is an adsorption belt conveyor, the rebound of SAP particles 19S can be suppressed by simply increasing the suction force of the suction section 11P on the substrate sheet 14. The inclination angle θ0 when inclined relative to the horizontal plane Hr in a manner that descends upstream in the conveying direction can be about 45 degrees, but is preferably about 30 degrees.

[0208] Figure 14 This is a diagram illustrating the suction opening 11su in the absorber manufacturing apparatus 50A of the first modified example. Furthermore, in Figure 14 In the diagram, the outline of the substrate sheet 14 is represented by dashed lines for reference.

[0209] In the absorbent manufacturing apparatus 50A of the first modification, similar to the absorbent manufacturing apparatus 50 described above, a suction section 11P is provided on the side opposite to the side where the substrate sheet 14 is located when viewed from the conveyor belt 11cn (support portion). However, unlike the absorbent manufacturing apparatus 500, in the absorbent manufacturing apparatus 50A, the suction opening 11su is not provided in the suction section 11P, but is provided on a separate conveyor belt 11cn1. Figure 14 As shown, multiple suction openings 11su are provided along the surrounding path of another conveyor belt 11cn1, and the position of the suction openings 11su also moves together with the movement of the other conveyor belt 11cn1.

[0210] In the absorbent manufacturing apparatus 50A, an additional conveyor belt 11cn1 is located between the conveyor belt 11cn and the suction section 11P, and moves in the same direction as the conveying direction of the conveyor belt 11cn. This suppresses wear on the conveyor belt 11cn caused by edge friction between the conveyor belt 11cn and the suction opening 11su, extending the service life of the conveyor belt 11cn. Furthermore, since the suction opening 11su is provided on the additional conveyor belt 11cn1 in the absorbent manufacturing apparatus 50A, when adhesive adheres to the suction opening 11su, only the additional conveyor belt 11cn1 needs to be replaced. Therefore, compared to the case where the suction opening 11su is located on the upper surface of the suction section 11P, replacement operations when adhesive adheres to the suction opening 11su can be performed more easily.

[0211] In the absorber manufacturing apparatus 50A, the additional conveyor belt 11cn1 and the conveyor belt 11cn move at the same speed, but the wrapping length of the additional conveyor belt 11cn1 is different from that of the conveyor belt 11cn. Therefore, the area where the conveyor belt 11cn rubs against the edge of the suction opening 11su changes with each wrapping. From this perspective, the lifespan of the conveyor belt 11cn can be extended. In addition, by staggering the position where the adhesive comes into contact with the conveyor belt 11cn in each wrapping, the clogging of the adhesive at the opening 11pn of the conveyor belt 11cn can be reduced. However, when the wrapping length of the conveyor belt 11cn is an integer multiple of the spacing PH of the multiple suction openings su, the position where the adhesive comes into contact with the conveyor belt 11cn will be any one of the suction openings su and will not be staggered. Therefore, the wrapping length of the conveyor belt 11cn needs to be an integer multiple of the spacing PH of the multiple suction openings su.

[0212] <<Structure of Absorber Manufacturing Apparatus 60>>

[0213] Next, based on Figure 15 and Figure 16 An absorber manufacturing apparatus 60 is described, which is a different embodiment from the absorber manufacturing apparatus 50 described above.

[0214] Figure 15 This is a schematic diagram showing the outline of the absorber manufacturing apparatus 60. Figure 16 This is a diagram illustrating the plate portion 11pt of the conveyor section 11y.

[0215] The basic structure of the absorber manufacturing apparatus 60 is the same as that of the absorber manufacturing apparatus 50 described above. The difference between the absorber manufacturing apparatus 60 and the absorber manufacturing apparatus 50 is that the conveying section 11y that conveys the substrate sheet 14 along the conveying direction has a rotating body 11tn instead of a conveyor belt 11cn. Furthermore, in the following description of the absorber manufacturing apparatus 60, the same reference numerals are used to refer to the same structures as in the absorber manufacturing apparatus 50, and the description of the parts common to the absorber manufacturing apparatus 50 is omitted.

[0216] like Figure 15 and Figure 16 As shown, in the absorber manufacturing apparatus 60, a plate portion 11pt is provided on the outer peripheral surface 11n of a rotating body 11tn that rotates in the conveying direction. The outer peripheral surface of the plate portion 11pt of the rotating body 11tn is used as the conveying surface of the substrate sheet 14. In other words, the plate portion 11pt of the rotating body 11tn conveys the substrate sheet 14 while supporting the central side surface of the rotating body 11tn (hereinafter referred to as "one surface"). Therefore, the plate portion 11pt of the rotating body 11tn may be referred to as a support portion.

[0217] In addition, Figure 15 and Figure 16 In the absorber manufacturing apparatus 60 shown, the conveying section 11y is a suction roller that conveys the substrate sheet 14 by suctioning it through a plurality of openings 11pn provided on the conveying surface of the plate section 11pt of the rotating body 11tn.

[0218] In this embodiment, an absorber containing a highly absorbent polymer is manufactured using the absorber manufacturing apparatus 60 with each of the above-described structures. As a method for manufacturing an absorber containing a highly absorbent polymer, the method first includes at least: a conveying step in which the substrate sheet 14 is conveyed while one side (the center side of the rotating body 11tn) is supported by a support portion (the plate portion 11pt of the rotating body 11tn); and a particle supply step in which SAP particles 19S are supplied to the other side of the substrate sheet 14 (the side opposite to the center side of the rotating body 11tn). Thus, an absorber having a highly absorbent polymer laminated on the substrate sheet 14 can be manufactured.

[0219] For example, a 11pt sheet is a perforated metal sheet, such as... Figure 16 As shown, the conveying surface of the plate portion 11pt has multiple openings 11pn. In the above-mentioned particle supply process, the suction unit 11P suctions the substrate sheet 14 through the multiple openings 11pn provided on the conveying surface of the plate portion 11pt.

[0220] Based on the above, in the conveying section 11y of the absorber manufacturing apparatus 60, the support section (the plate portion 11pt of the rotating body 11tn) has multiple openings 11pn. During the particle supply process, the substrate sheet 14 is drawn from one side (the side facing the center of the rotating body 11tn) through the multiple openings 11pn. This allows the manufacture of absorbers that form high weight-per-unit area regions 211 and low weight-per-unit area regions 212 surrounding each high weight-per-unit area region 211. Furthermore, although not shown, the diameter of the inscribed circle tangent to the openings 11pn of the plate portion 11pt is greater than or equal to the average particle size of the SAP particles. Therefore, SAP particles can be arranged in the recessed region 214 of the substrate sheet 14 as described above. In this embodiment, it is possible to easily manufacture an absorber with SAP that maintains thinness while providing good fit when worn.

[0221] Figure 17 This is a top view schematic diagram showing another example of a 11pt plate.

[0222] Figure 17 The plate portion 11pt shown is also a perforated metal plate with multiple openings. This plate portion 11pt has a first opening region 111 and a second opening region 112. For example... Figure 17 As shown, the second opening region 112 is adjacent to the first opening region 111 in the intersecting direction with the transport direction of the substrate sheet 14. Furthermore, the second opening region 112 may have multiple opening regions (two in this case) in the intersecting direction. However, there may also be only one second opening region 112.

[0223] exist Figure 17 In the plate portion 11pt shown, the opening ratio of the second opening region 112 is lower than that of the first opening region 111. Therefore, in the region being drawn through the second opening region 112, the formation of a high weight-per-unit area region 211 can be suppressed, and a channel region 215 with a lower weight-per-unit area for SAP than the high weight-per-unit area region 211 is formed. Furthermore, in the region being drawn through the first opening region 111, both a high weight-per-unit area region 211 and a low weight-per-unit area region 212 are formed.

[0224] In the particle supply process, the suction unit 11P draws particles from one side of the substrate sheet 14 (the side facing the center of the rotating body 11tn) via... Figure 17 The openings shown (first opening region 111 and second opening region 112) draw in the substrate sheet 14, thereby forming the aforementioned... Figure 8 The absorber 20B shown has a channel region 215.

[0225] Figure 18This diagram illustrates the supply of SAP particles and the discharge of adhesive in the absorbent manufacturing apparatus 60.

[0226] In the absorber manufacturing apparatus 60 of this embodiment, immediately after the process of supplying SAP particles from the particle supply unit 19 (particle supply process), the first adhesive discharge unit 15x1 (adhesive discharge unit 15D) discharges the adhesive 15H together with the air flow, and further downstream, the second adhesive discharge unit 15x2 (adhesive discharge unit 15D) discharges the adhesive 15H together with the air flow toward the substrate sheet 14 (adhesive discharge process).

[0227] like Figure 18 As shown, in the absorber manufacturing apparatus 60 of this embodiment, the adhesive 15H is also discharged from the outlets of each adhesive discharge section 15D (the first adhesive discharge section 15x1 and the second adhesive discharge section 15x2) in a predetermined discharge direction. Specifically, in the first adhesive discharge section 15x1, the adhesive 15H is discharged from the outlet of the first adhesive discharge section 15x1 in a predetermined discharge direction, such that the angle θ1 formed by the imaginary line extending from the discharge direction with respect to the tangent of the rotating body 11tn at the intersection of the imaginary line and the outer peripheral surface 11n of the rotating body 11tn is greater than 90 degrees, so that the upstream side of the discharge direction is inclined to the downstream side of the conveying direction. A portion of the supplied SAP particles 19S bounce back towards the downstream of the conveying direction. Therefore, compared to discharging the adhesive 15H perpendicular to the outer peripheral surface 11n, it is easier to push back the SAP particles 19S that bounce back to the downstream side by discharging the adhesive 15H from the downstream side in a manner that covers the SAP particles 19S.

[0228] In the absorbent manufacturing apparatus 60 of this embodiment, a second adhesive discharge section 15x2 is provided downstream of the first adhesive discharge section 15x1 in the conveying direction. Similar to the first adhesive discharge section 15x1, the second adhesive discharge section 15x2 discharges adhesive 15H from the discharge port in a predetermined discharge direction. Furthermore, for this discharge direction, the angle θ2 formed by the imaginary line extending the discharge direction of the second adhesive discharge section 15x2 with respect to the tangent of the rotating body 11tn at the intersection of this imaginary line and the outer peripheral surface 11n of the rotating body 11tn is greater than 90 degrees, causing the upstream side of the discharge direction 15d2 of the second adhesive discharge section 15x2 to be inclined towards the downstream side of the conveying direction. In the absorber manufacturing apparatus 60, by discharging adhesive 15H not only from the first adhesive discharge section 15x1 but also from the second adhesive discharge section 15x2 at that angle, it is easier to capture the rebound of SAP particles 19S that cannot be completely pushed back by adhesive 15H discharged from the first adhesive discharge section 15x1 alone.

[0229] Furthermore, preferably, the angle θ2 formed by the imaginary line extending the second adhesive discharge section 15x2 with respect to the tangent of the rotating body 11tn at the intersection of the imaginary line and the outer peripheral surface 11n of the rotating body 11tn is larger than the angle θ1 formed by the imaginary line extending the first adhesive discharge section 15x1 with respect to the tangent of the rotating body 11tn at the intersection of the imaginary line and the outer peripheral surface 11n of the rotating body 11tn (θ1 < θ2). Since the supplied SAP particles 19S tend to bounce back downstream in the conveying direction, by discharging the adhesive 15H at a more inclined angle from the second adhesive discharge section 15x2, which is positioned further downstream than the first adhesive discharge section 15x1, it is easier to capture the SAP particles 19S that fall to the downstream side.

[0230] Figure 19 This is a perspective view of the absorber manufacturing apparatus 60A of the second modification.

[0231] In the absorber manufacturing apparatus 60A of the second modification, the plate portion 11pt is composed of a substrate 118 and a mesh plate 119. For example... Figure 19 As shown, a suction opening 11su is provided on the substrate 118. In addition, an opening 11pn for suctioning the substrate sheet 14 is provided on the conveying surface of the mesh plate 119. In the absorbent manufacturing apparatus 60A, even if the adhesive becomes blocked at the opening 11pn, only the easily replaceable mesh plate 119 needs to be replaced, thus reducing replacement costs.

[0232] Figure 20 This is a top view schematic diagram showing another example of a substrate 118 with a plate portion of 11pt.

[0233] Figure 20 The basic structure of the substrate 118 shown is the same as described above. Figure 17 The plate portion 11pt shown is identical, having a first opening region 111 and a second opening region 112. For example... Figure 20 As shown, the second opening region 112 is adjacent to the first opening region 111 in the intersecting direction with the transport direction of the substrate sheet 14. Furthermore, the second opening region 112 may have multiple opening regions (two in this case) in the intersecting direction. However, there may also be only one second opening region 112.

[0234] exist Figure 20 In the plate portion 11pt shown, the opening ratio of the second opening region 112 is lower than that of the first opening region 111. Therefore, in the region being drawn through the second opening region 112, the formation of a high weight-per-unit area region 211 can be suppressed, and a channel region 215 with a lower weight-per-unit area for SAP than the high weight-per-unit area region 211 is formed. Furthermore, in the region being drawn through the first opening region 111, both a high weight-per-unit area region 211 and a low weight-per-unit area region 212 are formed.

[0235] In the particle supply process, the suction unit 11P draws particles from one side of the substrate sheet 14 (the side facing the center of the rotating body 11tn) via... Figure 20 The openings shown (first opening region 111 and second opening region 112) draw in the substrate sheet 14, thereby forming the aforementioned... Figure 8 The absorber 20B shown has a channel region 215.

[0236] Figure 21 This is a perspective view of the absorber manufacturing apparatus 60B of the third modification.

[0237] The absorbent manufacturing apparatus 60B of the third modification consists of a rotating body with suction openings 11su on its outer peripheral surface wound around a conveyor belt 11cn having multiple openings 11pn. As a method for manufacturing an absorbent containing a highly absorbent polymer using the absorbent manufacturing apparatus 60B, it first includes at least: a conveying step in which the substrate sheet 14 is conveyed while one side (the central side of the rotating body 11tn) is supported by a support (conveyor belt 11cn); and a particle supply step in which SAP particles 19S are supplied toward the other side of the substrate sheet 14 (the side opposite to the central side of the rotating body 11tn). Thus, an absorbent having a highly absorbent polymer laminated on the substrate sheet 14 can be manufactured.

[0238] The conveyor belt 11cm is, for example, a mesh belt, such as... Figure 21 As shown, multiple openings 11pn are provided on the conveying surface 11m of the conveyor belt 11cn. In the above-mentioned particle supply process, the suction unit 11P suctions the substrate sheet 14 through the multiple openings 11pn provided on the conveying surface 11m of the conveyor belt 11cn.

[0239] Based on the above, in the conveying section 11y of the absorber manufacturing apparatus 60B, the support section (conveyor belt 11cn) has multiple openings 11pn. During the particle supply process, the substrate sheet 14 is drawn from one side (the side facing the center of the rotating body 11tn) through the multiple openings 11pn. This allows the manufacture of absorbers that form high weight-per-unit area regions 211 and low weight-per-unit area regions 212 surrounding each high weight-per-unit area region 211. Furthermore, although not shown, the diameter of the inscribed circle tangent to the openings 11pn of the conveyor belt 11cn is greater than or equal to the average particle size of the SAP particles. Therefore, SAP particles can be arranged in the recessed region 214 of the substrate sheet 14 as described above. In this embodiment, it is possible to easily manufacture absorbers with SAP that maintain thinness while providing good fit when worn.

[0240] ===Others===

[0241] The above-described embodiments are intended to facilitate understanding of the present invention and are not intended to limit the scope of the invention. It is self-evident that the present invention can be modified and improved without departing from its spirit, and the present invention includes its equivalents.

[0242] Explanation of reference numerals in the attached figures

[0243] 1. Shorts-type disposable diaper (absorbent); 2. Side joint; 10. Absorbent body; 11x, 11y, conveying section; 11cn, 11cn1, conveyor belt; 11em, joint forming section; 11m, conveying surface; 11n, outer peripheral surface; 11P, suction section; 11pn, opening; 11pt, plate section; 11rn, conveying roller; 11su, suction opening; 11tn, rotating body; 12. Top sheet; 13a, back sheet (liquid-proof sheet); 13b, back sheet (outer packaging sheet); 14. Substrate sheet; 14S. Additional sheet; 15. Leak-proof wall section; 15D. Adhesive discharge section; 15H. Adhesive; 15x1. First adhesive discharge section; 15x2. Second adhesive discharge section; 16. Leak-proof wall elastic member; 17. Leg circumference elastic member; 18. Upstream side adhesive coating section; 19. Particle supply section; 19S. Superabsorbent polymer (SAP) particles; 20, 20A, 20B. Absorbent; 21. Skin side layer (absorbent core); 22. Intermediate layer (absorbent core); 2 3. Non-skin side layer (absorbent core); 24, 25. Core covering sheet; 26. Sheet; 27. SAP layer; 28. Bonding area; 29. ​​Non-bonding area; 30. Front waist section; 31. Skin side sheet; 32. Non-skin side sheet; 33. Waist elastic member; 34. Cover sheet; 40. Rear waist section; 40E. Part; 41. Skin side sheet; 42. Non-skin side sheet; 43. Waist elastic member; 44. Cover sheet; 50, 50A, 60, 60A. Absorbent body manufacturing device; 111. First opening Regions; 112, Second opening region; 113, Third opening region; 114, Non-opening region; 115, Fourth opening region; 116, Longitudinal member; 117, Transverse member; 118, Substrate; 119, Mesh plate; 142, End; 211, High weight per unit area region; 212, Low weight per unit area region; 212E, Low weight per unit area laminated region; 212N, Non-laminated region; 213, Extrusion section; 214, 214F, 214B, Recessed region; 215, Channel region.

Claims

1. An absorber having mutually orthogonal length, width, and thickness directions, and comprising a substrate sheet and a highly absorbent polymer laminated thereon, characterized in that, The absorber has a region with a high weight-to-area ratio of the highly absorbent polymer to its surroundings. The high weight-per-unit-area region is configured such that the point of maximum thickness in the thickness direction is intermittently located in the length and width directions. The maximum thickness is within 3 mm, and the interval between adjacent points that constitute the maximum thickness is less than 5 times the maximum thickness.

2. The absorber according to claim 1, characterized in that, The maximum thickness is within 2 mm, and the interval between adjacent points that constitute the maximum thickness is less than 4 times the maximum thickness.

3. The absorber according to claim 1, characterized in that, The high weight-per-unit-area region does not contain fibrous materials other than the highly absorbent polymer.

4. The absorber according to claim 1, characterized in that, When viewed from above, the diameter of the circumscribed circle of each of the multiple high unit area weight regions is 2 mm or more and 4 mm or less.

5. The absorber according to claim 1, characterized in that, The absorber has: Low weight-per-unit area laminated regions, in which the highly absorbent polymer is laminated between adjacent points that constitute the maximum thickness; and Non-layered regions, in which the highly absorbent polymer is not present between other adjacent points that constitute the maximum thickness.

6. The absorber according to claim 5, characterized in that, The low unit area weight stacked regions are intermittently arranged in the length direction and the width direction, and the non-stacked regions are intermittently arranged in the length direction and the width direction.

7. The absorber according to claim 6, characterized in that, When viewed from above, the largest diameter among the diameters of the inscribed circles that are internally tangent to the plurality of non-overlapping regions is less than or equal to the maximum thickness.

8. The absorber according to claim 6, characterized in that, The number of low-weight-per-unit-area-area-layered regions differs in each of the regions divided into three equal parts along the length direction, or the number of non-layered regions differs in each of the regions divided into three equal parts along the length direction.

9. The absorber according to claim 6, characterized in that, At the point that becomes the maximum thickness, The number of points located adjacent to the non-overlapping region on one or the other side of the width direction is greater than the number of points located adjacent to the non-overlapping region on one or the other side of the length direction.

10. The absorber according to claim 1, characterized in that, The absorber has an additional sheet positioned such that the highly absorbent polymer is sandwiched between it and the substrate sheet. The absorber has: A bonding region in which the substrate sheet and the additional sheet are bonded together at adjacent points that represent the maximum thickness. as well as Non-bonded areas, in which the substrate sheet and the other sheet are not bonded together between other adjacent points that are the points of maximum thickness.

11. The absorber according to claim 1, characterized in that, The difference between the highest and lowest points in the thickness direction on one side of the substrate sheet is different from the difference on the other side of the substrate sheet.

12. The absorber according to claim 11, characterized in that, On one side of the substrate sheet, there are non-laminated regions between adjacent points that represent the maximum thickness, where the highly absorbent polymer is absent. When viewed from above, the largest diameter among the diameters of the inscribed circles that are internally tangent to the plurality of non-overlapping regions is less than or equal to the difference between the two sides of the face.

13. The absorber according to claim 11, characterized in that, On one side of the substrate sheet, the weight of the highly absorbent polymer laminated below the highest point is more than 50% of the weight of the highly absorbent polymer laminated on the entire substrate sheet.

14. The absorber according to claim 11, characterized in that, When the region located below the midpoint between the highest and lowest points is defined as the concave region... When viewed from above, The total length of the plurality of recessed regions along an imaginary line passing through the center of the plurality of recessed regions along the length direction is more than 50% of the total length of the substrate sheet.

15. The absorber according to claim 11, characterized in that, When the region located below the midpoint between the highest and lowest points is defined as the concave region... When viewed from above, On an imaginary line passing through the center of the plurality of recessed regions along the width direction, the total length of the plurality of recessed regions is more than 50% of the total length of the substrate sheet.

16. The absorber according to claim 1, characterized in that, The absorber has a channel region in which the weight per unit area of ​​the highly absorbent polymer is lower than that of the region with high weight per unit area. The channel region extends along the length direction, and in the width direction, the width of the channel region is greater than the interval between adjacent points that constitute the maximum thickness.

17. The absorber according to claim 16, characterized in that, The trench area has multiple sections in the width direction.

18. The absorber according to claim 1, characterized in that, The absorber has an additional sheet positioned such that the highly absorbent polymer is sandwiched between it and the substrate sheet. In the length direction, the additional sheet and the substrate sheet are joined together in the thickness direction, on the outer side of the region where the highly absorbent polymer is located.

19. The absorber according to claim 1, characterized in that, An adhesive is provided between the substrate sheet and the highly absorbent polymer in the thickness direction.

20. The absorber according to claim 1, characterized in that, In the thickness direction, there is a fibrous material containing pulp at a position adjacent to the highly absorbent polymer.

21. The absorber according to claim 1, characterized in that, In the thickness direction, a fibrous material comprising pulp is provided at a position adjacent to the highly absorbent polymer, and an adhesive is provided between the fibrous material and the highly absorbent polymer.

22. An absorbent article having mutually orthogonal length, width, and thickness directions in an unfolded state, and having an absorbent body comprising an absorbent core, a substrate sheet, and a highly absorbent polymer laminated thereon, characterized in that... The absorber has a region with a high weight-to-area ratio of the highly absorbent polymer compared to its surroundings. The high weight-per-unit-area region is configured such that the point of maximum thickness in the thickness direction is intermittently located in the length and width directions. The maximum thickness is within 3 mm, and the interval between adjacent points that constitute the maximum thickness is less than 5 times the maximum thickness.

Images